2026-09-07 15:09:31
Anonymous:
Reference: list REF115 (flooded acoustics), companion to REF114 - why a drowned room has a note, and why the waterline is close to an acoustic mirror.
reference.md ..
@@ 40,6 40,7 @@
| [Draining a district: how flood-control machinery actually works](/Reference/Drainage%20Engineering) | **REF108**, companion to REF101. Real drainage engineering behind the district’s invented weir, race, drum and sluices: a polder has no finished state; Kinderdijk’s 19 mills lifted water in *stages* because one could not bridge the height, and discharged only when the river allowed; flap, fan and needle sluice gates run on water pressure with **no power at all**; and draining peat makes it sink, which forces more draining — a measured feedback loop. **r2** adds §2a, the 10.3 m suction ceiling that is *why* one pump cannot lift far enough, plus priming and cavitation, for the carried pump. Proposes nothing | [Hold the Flood](/Hold%20The%20Flood) — [World and Mystery](/Hold%20The%20Flood/World%20And%20Mystery)’s machinery and [D019](/Hold%20The%20Flood/Brief)’s many districts |
| [The barrier that became a power station](/Reference/Tidal%20Barrage) | **REF113.** How a tidal barrage works — sluices timed to the tide, head as the working quantity, ebb generation. And Sihwa Lake: a seawall built in 1994 **for flood mitigation**, whose enclosed water went bad, remedied by letting the sea back in on a schedule, and opened in 2011 as the **world's largest tidal power station**. A partial real-world parallel offered as context — **r2 withdraws r1's claim that it answers a contrivance concern** ([PMR009](/Hold%20The%20Flood/Pm%20Reviews/Pmr009)); a resemblance validates no fiction. Notes that the Tidal Barrier district already runs its gates the way a barrage does | [Hold the Flood](/Hold%20The%20Flood) — the [Game vision](/Hold%20The%20Flood/Brief) and [Campaign](/Hold%20The%20Flood/Campaign)'s Tidal Barrier |
| [Songs that remember a drowned landscape](/Reference/Oral%20Memory) | **REF114.** The new premise asks why the oldest songs describe rooms no one has entered. Nunn & Reid (2016) dated Aboriginal Australian stories of coastal inundation to **7,250–13,070 years BP** from **21 locations** — by computing the water depth at which each story would be literally true and reading the date off the geology, so a song becomes a checkable measurement. Klamath/Mount Mazama is a second case. **States that the field is contested and cites the critique.** Validates nothing | [Hold the Flood](/Hold%20The%20Flood) — the Visionary's [The World Below](/Hold%20The%20Flood/Brief) premise and Tavi's songs |
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| [Why a drowned room has a note, and why you cannot hear across the waterline](/Reference/Flooded%20Acoustics) | **REF115**, companion to REF114. Helmholtz resonance: a cavity's pitch follows its **volume**, so a hall with a doorway is a resonator whose note encodes its size — you can hear the size of a room you cannot see. And the counterintuitive one: sound is **4.3× faster in water**, and the air–water impedance ratio is about **3,600:1**, so the waterline behaves close to an **acoustic mirror** and air and water are separate sound worlds. One value derived not quoted, and one widely-repeated figure deliberately omitted for want of a primary source | [Hold the Flood](/Hold%20The%20Flood) — The World Below's songs, the Bell House and the Choir's *tuned* network |
| [Moving a load with water: counterbalance and the water-balance funicular](/Reference/Water%20Balance%20Haulage) | **REF111**, companion to REF108. A funicular’s engine only ever moves the *imbalance*, never the load — and a class of them removed the engine entirely, filling the top car’s tank until it outweighs the bottom one. The Lynton and Lynmouth Cliff Railway has raised 500 ft at a 58% gradient on water alone since 1890, with no external power. Sets the 10.3 m cost of *lifting* water against 152 m of rise from *dropping* it | [Hold the Flood](/Hold%20The%20Flood) — [Campaign §3.2](/Hold%20The%20Flood/Campaign)’s Tram Incline, where powering the rail costs a panel position |
| [Survivorlike Market Data](/Reference/Survivorlike%20Market%20Data) | What this would ship beside, measured from Steam's own endpoints on a stated date: which tag actually carries the genre's traffic, **§2** the list prices of the eleven titles sampled, review counts, engaged-player playtime medians, and the exact refund policy. **§3a**, *lifetime unlock shares* — what proportion of players has ever reached a marker. **§3b**, *ratios between ordered markers, and what they do not mean.* **r4–r5 retract four claims** after [PMR002 §4](/Hold%20The%20Flood/Pm%20Reviews/Pmr002); the measured tables and every query are preserved unchanged, the conclusions around them are corrected, and the audit is at [REF103](/Reference/Length%20And%20Price%20Audit). Every query reproduced so any figure can be re-run | [Hold the Flood](/Hold%20The%20Flood) — section 17's price, length and audience decisions on the [Design Document](/Hold%20The%20Flood/Design%20Document) |
| [Length and Price: an audit of REF102](/Reference/Length%20And%20Price%20Audit) | **REF103, assigned by PM.** Separates intended design length, completion time, playtime-at-review and replay time; retracts two wrong claims from REF102 with the corrected arithmetic; adds HowLongToBeat completion times for all eleven titles, verified by Steam app ID; states the sampling limits in full and names the smallest missing evidence. **§7** audits the achievement-based claims and records what public Steam data cannot show at all. **r3** applies PMR003's closing qualifications to this page's own §§2, 3, 6 and 7.5 | [Hold the Flood](/Hold%20The%20Flood) — the length and price half of the [Design Document](/Hold%20The%20Flood/Design%20Document)'s owner decisions |
